$860 Cheap Thai Airways International flights London (LHR) to Samui Intl. Airport (USM)

Set the "Price (lowest to highest)" filter on Expedia to search for cheap Thai Airways International return flights from $1,141 from LHR to USM. Affordable one-way tickets from $860 are available as well.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Check for Thai Airways International flights from LHR to USM about one month before you want to go. The most affordable time to book an international flight is generally 18 to 29 days ahead of your travel date when you can save 17% versus booking four to five months in advance. Regardless of fare class or itinerary, the best day of the week to book international airfare is usually Sunday. Friday can be the most expensive. Travelers who book on a Sunday can save 17% on average compared to those who book on a Friday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

Filter your results by "Early Morning" and "Morning" to find the earliest flights from LHR to USM. Heading off early means you're 20% less likely to experience cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.

Offering top-tier customer service, Thai Airways International is a top pick for many travelers flying from LHR to USM. Plus, as a Thai Royal Orchid Plus and One Key™ member booking through Expedia, you could earn OneKeyCash™* on eligible flights on top of your airline miles.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.